Condensing radiator system for refrigerator installations



P. A. SlDELL May 11, 1943.

CONDENSING RADIATOR SYSTEM FOR REFRIGERATOR INSTALLATIONS Filed May 10,1941 3 Sheets-Sheet 1 INVENTOR pl-l/A/P H. JIOEAA ATTO R N EY P. A.SIDELL May 11, 1943.

CONDENSING RADIATOR SYSTEM FOR REFRIGERATOR INSTALLATIONS Filed May 10,1941 3 Sheets-Sheet 2 77M& 1 INVENTOR Pa m/,0 H. 5/0544 ATTORNEYS.

y 1943- P. A. SIDELL 2,318,891

GONDENSING RADIATOR SYSTEM FOR REFRIGERATOR INSTALLATIONS Filed May 10,1941 a Sheets-Sheet 3 /0/ r x4 /0 k 7 9 Z INVENTOR All 2 5/05 4 ATORNEYS.

Patented May 11, 1943 STATES PATENT OFFICE CONDENSING RADIATOR SYSTEMFOR REFRIGERATOR INSTALLATIONS Application May 10, 1941, Serial No.392,851

32 Claims.

This invention relates to improvements in condensing radiator system forrefrigerator installation.

The invention has particular reference to household refrigeration, andit is the primary purpose of the invention to provide a novel andimproved means for distributing condenser load in such a manner as toenable an air cooled system to function efilciently without using forcedair circulation across the condenser. Forced air circulation isobjectionable not only because of the power required to operate the fanbut because of a certain amount of noise which it is desirable toeliminate in household refrigerators. Yet, in general, systems changedfrom forced air circulation to gravity air circulation across thecondenser, without other change, have had the back pressure on thecompressor so increased by the reduced efficiency of the condenser thatit has been necessary to reduce the size of the compressor piston tokeep the motor from being overloaded.

The present invention s'eeks to eliminate the air circulating fanwithout motor overload by storing during compressor operation such heatas cannot immediately be dissipated by convection currents and graduallydissipating such heat during that portion of the cycle when thecompressor is at rest, thereby distributing the dissipation of heat fromthe condenser over the entire cycle instead of attempting to dissipateall the heat as fast as it is generated.

It is a further purpose of the present invention to assist in pull downin a refrigerator installation by reducing head pressure, particularlyat the start of each cycle. It is also a purpose of the invention toreduce power consumption. Actual tests show a very substantial powerdecrease through the use of the invention. This is only partiallyattributable to the reduced head pressure and reduced condensertemperatures. In addition, and as a consequence of the reduced condensertemperature, it is possible greatly to reduce condenser volume wherebyfewer compression strokes are required to produce condenser pressure andless hot gas is unloaded from the condenser into the evaporator whenpressures are equalized. Moreover, the change in effective resistance inthe capillary tube (in a system employing such a tube), attributable tothe gradual rise in temperature occurring in the refrigerant of acondenser of the type herein disclosed, permits rapid refrigerant flowwith consequent high suction pressure and efilcient compressor operationfor a greater proportion of the cycle while nevertheless resulting inshorter overall periods of compressor operation in a given cycle.

More specifically, it is proposed to give domestic refrigeration unitsand like apparatus the benefits of liquid cooling as well as air coolingwithout requiring the plumbing connections which have heretoforerendered liquid cooling prohibitive for such installations. At the sametime it is proposed to take advantage of counter-flow of coolant in heatexchange with the condenser tubes by establishing thermo-syphoncirculation to and from a reserve suflicient so that the supply ofcoolant will not become heated to the temperature of the refrigerant inany ordinary cycle and will thus maintain the original temperaturedifferential instead of slowly heating the coolant in the mannercommonly experienced where a coil is merely immersed in a reservoir.

Ordinarily at least the tubes carrying the liquid coolant will be fullyexposed at all times to the air and preferably provided with fins withthe object of delivering heat to the air and only absorbing the excessby the circulating water. In one embodiment of the invention both therefrigerant tube and the coolant tube are exposed to the air and, beingdirectly bonded in side by side relation, each serves as an extendedradiating surface of the other.

An important object of the invention is the arrangement whereby theconvection currents of coolant reverse themselves, first flowing incounter-current relation to the refrigerant separately in eachsuccessive section of the condenser and, upon the conclusion of thecompression cycle, reversing themselves to flow in the same direction inwhich the refrigerant was flowing.

Further objects of the invention have to do with arrangements for forcedcirculation of the liquid coolant, preferably reversing the direction ofcirculation at the conclusion of the compression cycle in the samemanner in which the convection currents reverse their direction.

In the drawings:

Fig. 1 is a side elevation of an improved condenser system embodyingfeatures of the invention.

Fig. 2 is an end elevation of the condenser shown in Fig. 1, the pipesconnecting to the tank being shown in section.

Fig. 3 is a detail view taken in section on the line 3-3 of Fig. 1.

Fig. 4 is a detail view taken in section on the line 4-4 of Fig. 1.

Fig. 5 is a view on a reduced scale showing a preferred installation ina domestic refrigerator.

Fig. dis a view similar to Fig. 4 showing the connection between thecirculating coils and the storage reservoir slightly changed for thepurposes of the installation of Fig. 5.

Fig. 7 is a view taken on line 1-1 of Fig. 6 through the connections tothe storage reservoir and showing the storage reservoir in elevation.

Fig. 8 is a plan view of a. preferred condenser embodying the invention.

Fig. 9 shows the apparatus of Fig. 8 in side elevation and partially intransverse section.

Fig. 10 is an end elevation of the apparatus shown in Fig. 8, with aportion of the wall of the storage chamber broken away.

Fig. 11 is a detail view in cross section taken on the line ii-l i ofFig.9.

Fig. 12 is a diagram showing comparative timepressure curves showing theadvantage of my improved condenser over other convection cooledcondensers.

Fig. 13 is a set of time-pressure curves showing how my improvedcondenser modifies'the functioning of a capillary tube. 3

Figs. 14, 15 and 16 are diagrammaticviews illustrating portions of theapparatus in side elevation and other portions in section, anddiegrammatically illustrating the use of power circulation and thecontrols suitable therefor.

Like parts are identified by the same reference characters throughoutthe several views.

The general refrigerator hook-up may be that shown in my companionapplication Serial No. 329,140, filed April 11, 1940, and entitledRefrigeration systems. Any other type of evaporator may be used, thepresent invention pertaining primarily to that portion of the system inwhich heat is given off and condensation achieved.

From any suitable compressor, such as the motor compressor unit 5 ofFig. 5, the refrigerant arrives at the condensing radiator through apipe 8. The radiator is preferably of the continuous tube type, the tubeextending in a succession of convolutions which, in Fig. 1, areillustrated as disposed horizontally in a multiplicity of vertical heatdissipating fins 9. By way of exemplifying the invention I haveillustrated a condenser in which the condenser tube Ill which carriesthe refrigerant has six uniformly spaced horizontal convolutionsconnected by elbows ii at alternate ends of the device, there beingthree such elbows at the left in Fig. 1 and two at the right. Thisarrangement is conventional except that for the purposes of the presentinvention the tube I is flattened in the condenser proper where itpasses through the radiating fins 9 in order to extend its radiatingsurface horizontally. As shown in Fig. 3 eachflight or run of the tubel0 transversely of the condenser is of flattened oblate form in crosssection.

Preferably located immediately adjacent one end of the condenser is thestorage tank i which may be of any desired form or capacity, butpreferably has sufllcient capacity so that a liquid stored therein will,without undue rise of temperature, be adequate to absorb most of theheat given off by the refrigerant in the condenser tube It during thatportion of any given cycle of refrigerator operation in which the motorcompressor is functioning. The liquid stored in the reservoir i5 picksup the heat from the condenser tube It by means of a pipe or pipesbonded to the condenser tube and having both ends communicating with thereservoir l5 below the level of liquid therein and so arranged thatliquid will circulate by convection. The liquid used in the aerosoreservoir may be sweet water or may be any convenient anti-freezesolution or other liquid. prel- ;ralzly of such a nature as to have highspecific In order to promote gravity circulation of liquid between thereservoir i5 and the pipe in thermally conductive relation to thecondenser tube III, I preferably use not one but several such pipes eachof which communicates with the reservoir l5 separately at points nearthe top and bottom of the reservoir. each of said pipes being thereforesufliciently short so that its internal friction will not offer anyserious impediment to the gravity circulation of liquid between the pipeand the reservoir. One such pipe i6 leads from the top of reservoir l5and has a flattened portion ll thermally bonded to the top flight orrun-of the flattened condenser tube iii as shown in Fig. 3, the pipe I1and tube ill being of substantially identical thickness although pipe I!has a larger capacity due to a greater horizontal width than tube Ill.

The arrangement is such that the metal surfaces of the tube ill and theflattened portion ll of pipe l6 act respectively as fins for thedissipation of heat, each for the other. At the same time the bondedrelation between the pipe and the tube assures the transfer of heatconductively between the contents thereof.

Upon leaving the top flight of the condenser tube Ill the pipe i6communicates with the pipe portion I8 and is extended back through theflattened portion IS in bonded relation to the lowermost flight or runof the condenser tube ill and thence into the bottom of the reservoirl5.

Similarly, the pipe 20 opens from the top of the reservoir i5 and has aflattened portion 2| bonded to the flight or run of condenser tube itwhich is second from the top of the condenser, and a flattened portion22 bonded to that flight or run of condenser tube It which is secondfrom the bottom of the condenser, whereupon pipe 20 returns to thebottom of the reservoir I5.

Pipe 23 likewise leads from the top of reservoir I 5 and has a flattenedportion 24 bonded to the third flight or run of the condenser tube i0and thence returns with another flattened portion 25 bonded to thatportion of condenser tube II which is third from the bottom of thecondenser. Thence pipe 23 returns to the bottom of reservoir l5.

Thus each of the several pipes which carries the coolant liquid makesbut a single circuit of the condenser forth and back and is bonded bothin its outer traverse and its return traverse of the condenser to oneflight or run of the condenser tube. As above noted, this arrangement isgreatly to be preferred to the use of a single pipe coextensive with thecondenser tube solely because of reduced friction in each circulatingstream of coolant and a more direct passage of heated coolant to andfrom the storage reservoir l5.

Regardless of whether the coolant pipe is single or multiple, thecondenser is in effect duplex, the condenser tube l0 and the coolantpipe bonded thereto in each flight being in mutually heat conductiverelation to each other and to the several vertical fins 9.

The operation is as follows:

The refrigerant arrives at the condenser through pipe 8 and leaves itthrough pipe 2| after flowing through the condenser tube It. In passingthrough the condenser tube l0 heat is dissipated from the refrigerant byradiation and convection from the surface of the tube and from asiaeeithe extended sm'face represented by the flattened wall of the pipebonded thereto and from the ex tended surfaces provided by the verticalfins 8. As above noted, however, the convection currents of air whichmay be established in this manner are not adequate to wholly relieve thecompressor of head pressure in the condenser. Such head pressure isrelieved by the auxiliary supply of coolant in reservoir I which,circulating by gravity through the coolant pipe or pipes bonded to theflights of the condenser tube III, absorbs the excess heat beyond thatwhich can immediately be dissipated into the air. As fast as the coolantis heated in a pipe or pipes bonded to the condenser tube, it moves bygravity back into tank I5 and is replaced by coolant of lower temperammfrom the bottom of the reservoir. As above noted, the capacity of thereservoir is preferably such that during the normal period of compressoroperation the heat of compression will be re-' duced as fast as it isgenerated to a practicable working level by the combined continuousaction of the circulating air and the circulating coolant.

After the compressor operation has ceased, the circulation of thecoolant automatically reverses itself. The continued circulation of airinduced by the heat given off by the condenser continues to cool th finsand the surfaces of the tube III and the pipe or pipes in which thecoolant is carried through the condenser. As soon as the circulating airsufiiciently reduces the temperature of these metal surfaces so thatthese surfaces are at lower temperature than that of the heated coolantin the top of the reservoir I5, such heated coolant begins to give offits heat through the metal surfaces of the condenser and the coolantflows from the'top of the reservoir across the condenser and back at areduced temperature to the bottom of the reservoir. In this operationthe surfaces of the tube III act in effect as extended metal surfaces orfins for the coolant pipe or pipes bonded thereto, thus reversing thedirection of heat transfer originally existing. The coolant willcontinue to give off its heat until the compressor resumes operation oruntil the coolant is reduced to atmospheric temperature.

This arrangement provides a convenient way of connecting an air cooledrefrigeration system to a water cooling system without the use ofthermostats or valves if desired. While the system as disclosed iscomplete and self-contained and unitary and requires no externalconnections whatever for its successful operation, its efficiency may besomewhat increased in a permanent installation by connecting thereservoir I5 into series with any water supply pipe through which wateris intermittently drawn. For this purpose the reservoir may be providedwith a normally plugged inlet at 29 and a normally plugged outlet at 30which, whenever desired, may be connected in series with a toilet flushtank, for example. Any other household supply pipe may be connected tothe reservoir I5. Every time water is.

drawn through the household supply pipe in which reservoir I5 isconnected in series, the hot water in the reservoir will be immediatelydischarged therefrom and replaced by cold water from the system, therebyharmle'ssly and in- 1 stantly dissipating the heat from therefrigeration without the necessity for dissipation of such heat throughthe reverse circulation above described. No valves or thermostats arenecessary for the reason that the self-contained auxiliary heatdissipating system as disclosed will function in a perfectly normalmanner without being conmay ordinarily be sufficient to keep thecondenser super-cooled below atmospheric temperatures.

In the normal vertical or erect position of the condenser shown in Figs.1 to 4, there will ordinarily be ample air circulating by convectionover the condenser surfaces to assure the proper cooling of the device.However, where the conditions are extreme and it is desired toaccelerate the gravity circulation of air across the condenser surfaces,this may be done by either or both of two expedients disclosed in Fig.5. In the first place, the refrigerator cabinet 35 may be provided atits rear with a passage 36 in the nature of a chimney to create morehead or differential for promoting gravity circulation of the air heatedby the condenser. In the second place the condenser may be set at aslight angle as indicated at 31 in Fig. 5. Figs. 6 and '7 simply showthe connections to the reservoir I50 which may conveniently be employedif the condenser is set obliquely. The various pipes for the coolantwill pass more directly to the reservoir than the construction disclosedin Figs. 1 and 2 and 4. The pipe I6 simply enters the reservoir near itsfront side at the top and near its rear side at the bottom. the otherpipes progressively entering the reservoir nearer its center. As in thedisclosure of Fig. 1, it will be understood that the number of pipes andthe number of convolutions or flights of the condenser tube I0 isbroadly immaterial.

A preferred and simplified form of condenser is shown in Figs. 8 to 11.In this construction the condenser coils are inside of the coils inwhich the cooling liquid circulate to and from the tank I5I.

Three separate circulation pipes I I50, 200 and 230 are disposed side byside. Each of these communicates with the storage reservoir I5I near thetop of the reservoir and extends obliquely outwardly and downwardly andthence is bent upon itself and returned obliquely downwardly to thebottom of the reservoir. The relatively straight upper and lower runs ofthese pipes are provided with flns 90.

The refrigerant pipe from the compressor is shown at 80. It enters thereservoir I5I from the back as shown in Figs. 8 and 10, and traversingthe reservoir I5I extends directly into the coolant pipe IIiIl, throughwhich it passes.

Issuing from the lower end of coolant pipe I60, the refrigerantconduitagain emerges at 8| from the rear of the reservoir and by means fcoupling 82 it is connected behind the reservoir to enter pipe 83 whichpasses angularly up the rear of the reservoir and re-ent'ers the rearwall of the reservoir and is led through the coolant pipe 200 from thetop of the reservoir downwardly through such pipe and back into thereservoir at its bottom.

This section of the condenser conduit emerges from the back of thereservoir at 84 and thence passes obliquely up the back of the reservoirand is coupled at 85 to another continuing section 86 of the refrigerantconduit which re-enters-the back of the reservoir at the top in registrywith coolant pipe 230. Running through the interior of the pipe 230 inthe manner best shown in Fig. 9, this section of the condenser conduit86 returns from the lower end of pipe 230 into the bottom of thereservoir and issues through the back of the reservoir at 88, where itconnects to the capillary tube 89 leading to the evaporator in the usualmanner.

nected to any circulatory water systemyand yet the normal use of waterin the circulating system a While the respective flights Cl, 88 and I01' the continuous tube condenser are shown centered within the coolantpipes, it will be understood that in actual practice the pipes andcondenser tubes will ordinarily be in metallic contact and may be bondedtogether if desired. While the refrigerant tubes are not exposed to theair directly. as in the device shown in Fig. 1, the emciency of heatdelivery is very high in this apparatus and the convection currents ofcoolant between the reservoir Iii and the several pipe I", 2". and 230are unobstructed and flow with considerable rapidity. The chief reasonfor preferring this construction, however, is the fact that it not onlycosts considerably less to make than the condenser shown in Fig. l, butrequires very materially less power for its operation.

Fig. 12 shows comparative curves of temperature (or head pressure) atthe condenser. Curve A is obtained in a refrigerator system using aconventional convection tube condenser radiator with twelve passes-thatis to say, twelve flights or runs of tube exposed to the air.CurveBshows the temperature and head pressure curve obtained with thesame identical system except for the substitution of the condenser shownin Figs. 8 to 11 with only six passes. The power consumption per cycleis reduced in actual practice by 20% and more and the cost is reduced byone third.

In addition, the use of a shorter capillary tube is made possible at 89because of the fact that the temperature in the condenser builds upgradually as the coolant therein becomes heated.

At the start of compressor operation it is eflicient to keep the flow ofrefrigerant to the evaporator rapid. This keeps the evaporator pressurehigh and consequently furnishes refrigerant at a high back pressure tothe compressor to maintain its volumetric efllciency high. Also therapid flow fills the evaporator more completely and in less time withliquid refrigerant; Such rapid flow can be accomplished with a shortcapillary tube but the objection to such a short capillary tube lies inthe fact that a short capillary in an ordinary organization keepscondenser pressure low by exhausting a substantial percentage of thegaseous refrigerant into the evaporator and the operating cycle isconsiderably lengthened, thereby increasing power requirements andreducing efllciency.

However, in the present system the capillary 89 is made very short, thusgiving high initial flow to the evaporator. But as the condensertemperature increases due to the gradual heating up of the coolant inthe device herein disclosed, the resistance of the capillary to the flowof the warmer refrigerant is automatically increased whereby thepressure curve at the evaporator is greatly shortened and rendered morenearly vertical, thus increasing efliciency. As the back pressure at theevaporator is reduced and the volumetric emciency and output of thecompressor are correspondingly lowered, the capillary, even thoughshort,.has a sufficient increase in resistance consequent upon itsincreased temperature so that this compensates for the reduced input ofrefrigerant to maintain condenser pressure high and approximatelyuniform.

In accordance with the foregoing, Fig. 13 is a chart showing at C thecurve resulting from the use of a fairly short capillary in aconventional refrigerating system not embodying the present invention.The curve D shows a longer capillary and the curve E a very longcapillary. The curves D and E indicate a shorter operating cycle but donot hold the evaporator pressure up as well at the start of the cycleand consequently are not as nearly vertical as is the curve F whichshows the result of the use of a very short capillary with a condenserof the type herein disclosed.

As a result of this construction, the condenser volume is reduced, itscost isreduced, the compressor power requirements are reduced. Yet theetllciency of the refrigeration system as a whole is increased. Thesystem does its work with a materially reduced operating cycle.

By way of example, the average period of operation under givencircumstances with a conventional system using forced draft for coolingthe condenser, was found to be 2 minutes and 45 seconds. Using aconventional convection cooled condenser, the circumstances and systembeing otherwise identical, the running time was 3 minutes and 10seconds. The system embodying the condenser disclosed in Fig. 1 of thisapplication had a running time of 2 minutes and 4 seconds. The systemusing a condenser and shortened capillary in accordance with thedisclosure of Figs. 8 to 11 had a running time of only 1 minute and 54seconds under otherwise identical circumstances.

It will be understood that the storage tank III shown in Figs. 8 and 10may, if desired, be provided with water connections like that shown inFig. 1. Both, however, are normally adapted to function as closedsystems even when provision is made for periodically interchanging thecoolant -n tne system through the water connections as above described.

It is also possible by increasing the vapor space above the water levelin either reservoir, to use in the system a cooling liquid which isevaporable at the temperatures produced in operation, thereby employingthe resulting bubbles in the pipes I. or liil to accelerate flow andconvection cooling while also accelerating the cooling by theevaporation of the coolant during the operating portion of the cycle.The arrangement will be such that the coolant evaporated and thuscontaining in the form of latent heat, the heat energy of the.

compressed refrigerant, will be condensed in the top of the reservoir,the system remaining completely closed.

In practice I employ in the reservoir I5, I50, or l5l, water which haschemicals dissolved therein to prevent freezing and corrosion. Asurprisingly small amount of coolant is required due to the fact thatmuch of the heat of the compressed refrigerant is delivered off by fins90 from the coolant before the coolant ever enters the reservoir.

The cooling action of the coolant is very effective upon the refrigerantdue partly to the fact that the circulatory paths upon which the coolantmoves are very short. Upon each such path the convection currentsestablished during the operation of the compressor are such that theflow of coolant is counter-current to the flow of refrigerant. Thecoolant heated in any given cycle is not recirculated through thesepassages in the a like amount of heat in a given amount of time to airpassing over the condenser, the air will be heated to a highertemperature, which could only be obtained by a combination of anincrease in condenser surface and volume and an increase in condensertemperature, with the result that the refrigerant leaving the condenserwould not be as cool as in the use of the present invention and adefinite increase in head pressure would be observed as compared withthat existing in the use of the device here disclosed.

Moreover, since the air picks up' heat relatively slowly from aconventional static condenser, not only a large surface area is requiredbut also high internal volume, in order to allow time for the gas todissipate its heat. The high specific heat of the liquid and itsextremely high density in comparison to that of air, permits the heatfrom the refrigerant to be dissipated very rapidly with a greatlyreduced internal condenser volume. In actual practice the condenservolume is only about one-fifth of .that required in the conventionalsystem. As a result, only one-fifth as much hot gas can, under anycircumstances, be bled into the evaporator after the compressor shutsoil, and only about one-fifth as much can be bled into the evaporatorduring the start of a new cycle, the condenser pressure being restoredfive times as fast as in the conventional system. This representsfurther substantial savings, because all heat blown into the evaporatormust again be pumped out and the volume of gas bled from the condensermust be replaced at the start of a new cycle.

Where desired, the coolant may be positively circulated by power,various arrangements for this purpose being illustrated diagrammaticallyin Figs. 14 to 16. Even where power is used, it is preferred that thedirection of circulation of the coolant should reverse at the conclusionof the compression portion of the refrigerator cycle. At this time thestorage reservoir will ordinarily have heated coolant in its upperportion and some remaining relatively cold coolant in its power portion.If th circulation were to continue in the same direction during the oficycle, the cold coolant would have to pass through the coils before thehot coolant would reach the coils to be chilled thereby. By reversingthe cycle it is possible to deliver the hottest portion of the coolantimmediately to the radiator.

The reservoir I52 will be understood to correspond to the reservoirsindicated at I5, I50, and NH. The pipe I62 provides a closed circuit forcoolant in which the reservoir is included, as is also a pump 92 drivenby motor 93. The condenser tube 01 passes through portions of pipe I62provided with fins 9|.

At 94 there is illustrated an electric motor which is intended torepresent the motor which drives th refrigeration compressor (notshown). In the motor circuit. either in series or parallel, is connectedthe coil 95 of. a relay having an armature 96 which carries a switchcontactor 91. Fig. 14 shows the position of the switchcontactor when thecompressor motor 99 is in operation and the relay coil 95 is energized.In this posi-' tion the contactor 91 closes a circuit to the pump motor93 to drive the pump in a direction such 'that the coolant is pumpedfrom the bottom of the reservoir I52 into the lower end of the pipe I92,thereby displacing from the top of the pipe coolant heated by the hotrefrigerant in the tube 81. For convenience of illustration, the pump isnaturally shown very much larger in proportion to the size of theradiator than it would actually be in practice.

When the circuit to the refrigerator motor 94 is de-energized, thede-energization of relay coil 95 allows the contactor 91 to drop,thereby closing the circuit between contact points 98 which are in areversing circuit for the pump motor 93, such circuit also including inseries the thermostat 99. If the thermostat is cold at the time therelay is de-energized, th reversing circuit to the pump motor 93 willremain open and the pump will come to rest. However, if thethermostat-has become heated due to the warming up of the entireradiator, the circuit controlled by the thermostat will be closed whenthe relay coil 95 is de-energized, with the result that the pump motor93 will be reversed and will continue in operation, pumping hotcoolantfrom the top of th reservoir I52, until the coolant issufliciently cooled in the radiator to permit the thermostatic switch 99to open, thereby breaking the pump motor circuit.

Fig. 15 shows a generally similar arrangement differing from that abovedescribed only in that the pump motor is time controlled instead ofbeing controlled by a thermostatic switch for its reverse operation. Inthis device there is connected with reversing contacts 98 of the relay,an electrically conductive segment I over which operates a brush IIIIfrictionally mounted on a shaft I02 which is connected by belt I03 tothe motor 92. At one end of segment I00 there is insulation I04providing a non-conCuctive dead spot. Near the other end of the segmentis a stop at I05 for arresting the movement of the brush arm i0I, thefrictional connection between such arm and shaft I02 permitting thecontinued op- ,eration of the shaft after the brush arm engages belt I03will drive the brush IIII from the dead spot I04 in a clockwisedirection toward a position of engagement with stop I05. The brush willactually reach the stop only if the operation of the refrigerator motor94 is long continued. Otherwise the brush will come to rest at someintermediate point, it being understood that any desired reducinggearing (not shown) will be introduced in practice between the motor 93and the brush carrying shaft I02.

At the end of the compression cycle the refrigerator motor 94 will cometo rest and the relay coil 95 will be deenergized, thereby closing thecircuit between contacts 98 of the pump motor reversing line. Thereversing circuit will be completed through the brush IM and the segmentI00, thereby operating the pump motor 93 in reverse to expel heatedcoolant from the top of the reservoir I52 and returning the relativelycolder liquid from the bottom of the radiator into the bottom of thereservoir. This circulat on will continue until the brush I M reachesthe dead spot I04 at the end of the segment I00, the brush beingoperated in a counter-clockwise direction during reverse operation ofmotor 93. When the brush runs onto the dead spot the operation of thepump motor will be discontinued and the parts will all remain at restuntil the refrigerator motor is re-energized, at which time the pumpwill again be driven forwardly and the brush I02 propelled clockwisetoward the stop I as above described.

In the construction shown in Fig. 16, the motor 930 operates in but onedirection, but the direction of flow of the coolant is changed by areversing valve H0. While this valve might be connected for timeoperation as suggested in Fig. 15, I have shown it controlled foractuation to one position by a relay system and controlled for actuationto its opposite position by the thermostatic switch 99.

The valve III) as illustrated, has an annular passage III aligned withports which communicate with pipes H2 and H3. while a similar annularpassage at II 4 is aligned with pipes H5 and H8, this arrangementpermitting circulation of hot coolant from the bottom of reservoir I52into pipes H2, H3, H5, H6,and I62, in sequence. Valve H0 is drawn to theposition shown by the tension of spring III. The motor 930 is energizedthrough the operation of relay coil 950 which is connected in thecircuit of the refrigerator motor 94 to attract the armature 910 whenthe refrigerator motor is in operation. The armature 910, directedagainst the tension of spring H8, operates contacts H9 and I intoengagement with stationary contacts connected in series with the motor930.

When the refrigerator motor 94 is de-energlzed and comes to rest. thearmature 910 is attracted by spring I I8 toward the left as viewed inFig.

16, whereby the contactors H9 and I20 energized from the line are movedinto engagement with stationary terminals I2I and I22 respectively,while contactor I23, energized from terminal I22, moves into engagementwith terminal I24. This arrangement maintains the circuit connections tothe pump motor 930 to keep the pump 92 in operation in the samedirection. At the same time a circuit is completed through the solenoidI25, the armature I25 of which is connected to the valve IIII, wherebythe valve is drawn to the right against the tension of spring III tobring the crossed conduits I21 and I28 into registry with the severalpipes above described, in such a way as to reverse the direction ofpump-induced circulation through such pipes,

the pipe H2 being cross-connected to pipe H5 through conduit I28, andthe pipe I I5 being cross-connected by conduit I21 to pipe I I3.

Such continued operation of the pump motor is, as in the Fig. 14construction, contingent upon the closed status of the thermostaticswitch 99. and as soon as the coolant has been cooled sufiiciently topermit this thermostatic switch to open, the pump motor will bede-energized as will the solenoid I25, and the parts will all remain atrest until the operation of the refrigerator motor 94 is againcommenced.

I claim:

i. In a condenser system, the combination with a storage reservoir forcoolant and a coolant circulatory pipe connected to the reservoir atvertically spaced points for convection circulation of coolanttherethrough. of a refrigerant condenser pipe in heat exchange relationto the first men tioned pipe and coolant therein, the system beingarranged that the convection circulation of coolant in the firstmentioned pipe reverses itself when the refrigerant ceases to give oilexcessive heat to the coolant.

2. In a refrigeration system, the combination with a refrigerantcondenser pipe adapted to handle refrigerant in a predetermineddirection during the compression cycle, of a circulatory pipe for liquidcoolant in heat exchange relation to the condenser pipe, and meansincluding a reservoir for coolant connected in substantially closedcircuit arrangement to said coolant pipe for the circulation of coolantin counterfiow relation to the refrigerant in said first mentioned pipeduring the heating cycle and for the reverse direction of coolantcirculation through the coolant pipe upon the conclusion of the heatingcycle.

3. In a condenser system, the combination with a refrigerant condenserpipe, of a reservoir for coolant and a coolant circulatory pipeconnected to the reservoir at vertically spaced points and in heatexchange relation to a portion of the refrigerant condenser pipe, asecond coolant circulatory pipe connected to the reservoir at verticallyspaced points for convection circulation of coolant therethrough and inoperative heat exchange relation to another portion of said refrigerantcondenser pipe, at least one of said pipes being provided with radiatingheat dissipating means, and the capacity of the reservoir being suchthat the heat rejected by refrigerant in the condenser pipe and notradiated by said means is delivered successively from said condenserpipe to coolant in the first and second circulatory pipes and thencedelivered by convection to the top portion of said reservoir. the heatedcoolant in said circulatory pipes being replaced by cooler liquid fromthe bottom of said reservoir without recirculation of heated coolantduring a given period of heat rejection from the refrigerant.

4. In a condenser system, the combination with a refrigerant condenserpipe having a portion extending in a direction having a vertical compo!nent, of a storage reservoir for coolant, a coolant, pipe connected atvertically spaced points with the reservoir and operatively associatedin heat exchange relation to the refrigerant condenser pipe portionaforesaid, the refrigerant in 'flie condenser pipe being subject tocyclic periods of compression and heat rejection and the capacity of thereservoir being such as to provide replacement by convection circulationthrough the coolant pipe of heated coolant with cold coolant withoutrecirculation in any given cycle of heat rejection of any substantialquantity of coolant previously heated during such cycle.

5. In a refrigerating circuit including a compressor and evaporator, acondenser system comprising the combination with a reservoir, of a pairof pipes one of which is inside of the other, one of said pipescommunicating at, vertically spaced points with the reservoir and theother,

comprising a refrigerant tube connected between the compressor andevaporator in said circuit, the reservoir and the pipe communicatingthere with being filled with coolant for convection circulation and theexternal pipe being exposedto circulation of air.

6. In a refrigeration system, comprising in operative closed circuitconnection a compressor, a condenser, a pressure reducing means, and anevaporator, the combination in a condenser system with a coolantreservoir and a pine connected at vertically spaced points to thereservoir for convection circulation of coolant therethrough, of acondenser pipe In said circuit for refrigerant in thermally conductiverelation to the first mentioned pipe and the coolant therein contained,the condenser of said refrigeration system comprising the condenser pipeaforesaid at least one of said pipes being exposed to convectioncurrents of air and provided with flns for dissipating heat.

'1. In a condenser system, the combination with a reservoir and a seriesof coolant pipes each connected with the reservoir at vertically spacedpoints, of a continuous condenser pipe for refrigerant in heat exchangerelation to portions of said first mentioned pipes in series, at leastone of said pipes being exposed to convection currents of air.

8. The combination in a condenser with a series of refrigerant tubeflights in spaced relation, of a reservoir and a coolant pipecommunicating with said reservoir at vertically spaced points thereinfor gravity circulation of coolant between the reservoir and the pipe,said pipe including a flight extending outwardly from the reservoir inheat exchange relation to one of said tube flights, and a return flightleading back to the reservoir in heat exchange relation to another ofsaid tube flights.

9. The combination in a condenser, of a continuous refrigerant tubeextending to and fro across the condenser in a series of flights, of areservoir, a plurality of separate pipes each connected for gravitycirculation between vertically spaced points of said reservoir, eachsuch pipe including forth and back pipe flights in bonded relation toseparate convolutions of said tube.

10. The combination in a condenser with a continuous refrigerantcondensing tube extending in convolutions forth and back across thecondenser of a. series of flights exposed to air circulation, of areservoir, a first pipe connected at vertically spaced points to saidreservoir for convection circulation of coolant between the reservoirand pipe, said pipe including flights respectively bonded to the firstand last flights of said refrigerant tube, and a second pipe likewisehaving its ends communicating with said reservoir at vertically spacedpoints for gravity circulation of coolant between the reservoir and thesecond pipe, said second pipe having forth and back flights respectivelybonded to intermediate flights of said refrigerant tube.

11, In a condenser system, the combination with an upright reservoir, ofan obliquely disposed condenser comprising a continuous tube in a seriesof convolutions including a plurality of flights, and a coolant pipebonded to a plurality of flights of said condenser tu-be and ex tendingfrom an upper portion of said reservoir adjacent one side thereofobliquely to a lower portion of said reservoir adjacent the other sidethereof.

12. In a condenser system, the combination to edge with flattenedportions of said tube to provide surfaces elongated transversely of saidfins, said pipe being in thermally conductive relation to said flns andexposed to air circulation therebetween.

.14. A condenser comprising the combination with a continuous condensertube convoluted in a series of flights, of a reservoir and a coolantpipe communicating at vertically spaced points with said reservoir forgravity circulation of coolant between the reservoir and pipe, said pipehaving spaced flights paralleling remote flights of said condenser tubeand flattened and bonded edgewise with said parallel condenser tubeflights, and a second pipe likewise communicating at vertically spacedpoints with said reservoir for gravity circulation of coolant betweenthe reservoir and the second pipe, said second pipe having flatenedportions-bonded edgewise to flights of said condenser tube interveningin said series between the condenser tube flights to which the flattenedportions of the first pipe are bonded.

15. A condenser system comprising the combination with a reservoircontaining coolant, of a series of pipes communicating with thereservoir at vertically spaced points for convection circulation ofcoolant through said pipes, and a refrigerant tube extending through thereservoir into one of said pipes, through said pipe and back through thereservoir and into another of said pipes, and through the last mentionedpipe and through the reservoir, said pipesbeing finned externally of thereservoir for air cooling.

' 16. A condenser radiator system comprising the combination with areservoir for coolant and at least one coolant pipe connected with saidreservoir at vertically spaced points for gravity circulation, of acondenser tube for refrigerant having at least one flight in thermallyconductive relation to said pipe and the coolant therein contained, theassembly of said flight and pipe being exposed for air cooling and saidreservoir and pipe being adapted to function as a closed system forabsorbing excess heat during a part of the refrigeration cycle and fordelivering oil such heat to the air during another part of said cycle.and

connections at said reservoir whereby said reservoir may be connected inseries into a water main for periodical exchange of its contents whenwater is drawn through said main.

17. A condenser system comprising the combination of a reservoir and aplurality of laterally with a refrigerant tube, of a coolant tube oflarger cross-sectional area than the refrigerant tube and flattened tosubstantially the same thickness, said tubes being bonded together withtheir respective surfaces representing generally streamlined extensions,each of the other.

13. In a condenser, the combination with a series of spaced fins, of acondenser tube extending in convolutions forth and back across said finsand having flattened portions extending transversely between said finsand exposed to air circulation therebetween, said flattered tubeportions being in thermally conductive relation to the'respective flnsand at least one coolant pipe having flattened portions bonded edgeadjacent pipes of V-shaped form each connected to the reservoir atvertically spaced points and projecting laterally with their respectiveapices remote from the reservoir for gravity circulation of coolantbetween the reservoir and said pipes, and a continuous refrigerant tubeextending through said pipes in series entering each at points near thetop of the reservoir and leaving each near the bottom, wherebyconvection currents established in said pipes by heat rejected by saidtube flow counter to the path of refrigerant in said tube.

18. In a refrigeration system of the type having an evaporator, acompressor, a condenser, and a capillary tube leadingfrom the condenserto the evaporator, the combination with a relatively short capillary, ofa condenser including a condenser tube for the refrigerant leading tosaid capil1ary,.a coolant pipe inthermally conduct ve relati n to thetube and arranged for gravity circulation of coolant, and a coolantreservoir with which said pipe communicates at veriicaly spaced points,said reservoir and pipe containing coolant and the portion of saidcondenser comprising said pipe and tube assembly being exposed to aircirculation, whereby said assembly delivers heat to the air, the coolantbeing adapted to absorb heat from the refrigerant in said tube duringthe operation of the compressor but gradually to warm up if the cycle ofcompressor operation is prolonged, the size of the capillary being suchas to discharge refrigerant freely during the initial period ofcompressor operation while the coolant remains cool but to retard theflow of refrigerant as the temperature of the refrigerant rises due tothe heating of the coolant.

19. A condenser radiator system adapted for use in a refrigerationcircuit having a compressor and evaporator operable in cycles ofcompressor operation and rest, said system comprising the combinationwith a reservoir for coolant and at least one coolant pipe connectedwith said reservoir at vertically spaced points for gravity circulation,of a condenser tube for refrigerant having at least one flight inthermally conductive relation to said pipe and the coolant thereincontained, the assembly of said flight and pipe being exposed for aircooling and said reservoir and pipe being adapted to function as aclosed system for absorbing excess heat during a part of the compressoroperation cycle and for delivering of! such heat to the air duringanother part of said cycle.

20. A cooling method comprising the establishment of a current of fluidto be cooled, the circulation of a coolant in heat exchange relation tosaid current from a coolant reservoir and back to said reservoir in asubstantially closed circuit for a period normally insufiicient todisplace all of the coolant from the reservoir, and the reversal of thedirection of coolant circulation at the conclusion of said period.

21. A method of cooling which comprisesthe establishment of a current offluid to be cooled, the circulation in a closed circuit of coolant inheat exchange relation to said fluid from a supply of such coolant andback to such supply while rejecting heat by radiation from the coolantthus circulated, continuing such circulation of coolant in one directionuntil the temperature of the fluid ator during a portion of the cycle inwhich heat is being developed in said fluid and for delivering theheated coolant back to said radiator and receiving colder coolant fromsaid radiator during the remaining portion of the cycle.

24. The combination with a tube for a fluid V periodically requiringheat rejection, of a closed to be cooled substantially reaches a peak,and

thereafter reversing the direction of circulation of coolant whereby thehottest portion of such coolant rejects its heat.

22. A method of cooling refrigerant in a condenser radiator during thecompression portion of a refrigerator cycle, such method including thedelivery of the compressed and heated refrigerant through a condenserradiator, the circulation in a substantially closed path of the coolestportion of asupply of coolant through the same radiator in heat exchangerelation to the refrigerant therein 'and returning the heated coolant tothe supply and, at the conclusion of the compression cycle, reversingthe flow of coolant circulation whereby to deliver heated coolantdirectly to said radiator from said supply while restoring coolant at arelatively lower temperature from said radiator to said supply.

23. The combination with a condenser radiator comprising a closedcircuit path for coolant, a

substantial storage capacity of said path being located outside of saidradiator, said radiator also comprising a series-connected path forfluid intermittently requiring cooling in a predetermined cycle, saidclosed circuit coolant path constituting means for delivering relativelycold coolant to said radiator in heat exchange relation to said fluidand receiving heated coolant from said radicircuit conduit for coolant,a portion of said circuit being in heat exchange relation to said tube,said circuit portion and tube constituting a radiator, and the portionof said circuit outside of said radiator comprising coolant storagemeans adapted to receive and deliver coolant to and from said radiator,means for mechanically circulating coolant, and means for reversing thedirection of coolant circulation.

25. The combination with a tube for fluid requiring cooling, of asubstantially closed circuit conduit having a coolant storage portionand another portion in heat exchange relation to said tube, means formechanically circulating coolant in said conduit in a direction todeliver the hottest coolant into said storage portion, and means forreversing the direction of coolant circulation in said conduit in adirection to deliver the hottest coolant in said conduit from saidstorage portion.

26. The device of claim 25 in which the circulating means comprises amotor driven pump and the reversing means comprises a reversing controlfor the motor of said pump.

27. The device of claim 25 in which the coolant circulating meanscomprises a motor driven pump and the reversing means comprises areversing valve having cross-connections operatively adjustable todirect the pump output in opposite directions in said circuit.

28. The device of claim 25 in which the circulating means comprises amotor driven pump and the means for reversing the direction ofcirculation comprises a motor reversing connection, means for actuatingsaid connection to reverse the direction of pump operation, and athermostat exposed to temperatures developed in the heat exchangeportion of the conduit and connected to complete, when warm, a reversingcircuit of said motor driven pump.

29. The combination with a conduit for a fluid to be cooled, of asubstantially closed circuit conduit for coolant, said conduits havingportions in mutual heat exchange relation, of a motor driven pump forcirculating coolant in the closed circuit conduit, means for reversingthe direction of circulation of fluid in said conduit, and means forlimiting the continued operation of the pump to a predetermined periodafter the reversal of current direction.

30. In a refrigeration system, the combination with a condensing tubeand fln means constituting extended heat rejecting surfaces thereof,said tube being adapted to receive and cool hot refrigerant during apredetermined compression cycle, of a conduit for coolant in heatexchange relation to the tube and the fln means, of a coolant reservoirwith upper and lower portions of which said conduit communicates for theconvection circulation of coolant. the storage capacity of the reservoirbeing sumcient to receive substantially all of the coolant heated duringthe aforesaid compression cycle, the coolant so received into thereservoir entering the reservoir through the upper connection of saidconduit therewith and being replaced in said conduit by coolant receivedtemperature of the coolant faster than such coolant loses heat in thereservoir, whereby a reverse convection current is established in theconduit in a direction such that the conduit receives the relativelyhigh temperatured coolant from the upper connection of the conduit withthe reservoir and returns coolant at a relatively lower temperaturethrough the lower connection of the conduit with the reservoir.

31. In a refrigeration system of the type having an evaporator, acompressor, a condenser, and a capillary tube affording communicationfrom the condenser to the evaporator, the combination with a compressorhaving a motor, means controlling the compressor motor for theintermittent operation thereof, and a relatively short capillary, of acondenser including a condenser tube for the refrigerant leading to thecapillary, said condenser tube being provided separately with means forheat rejection by radiation and by conduction, the means for heatrejection by radiation comprising extended heat radiating surfacesinadequate to dispose of refrigerant heat as fast as such heat isdeveloped during periods of compressor motor operation, the means forheat rejection by conduction comprising heat absorbing means inconductive relation to said condenser tube and of such heat absorbingcapacity as to receive heat in substantial quantities from said tube andto .become slowly heated during compressor operation, said heatabsorbing means being also in' heat conductive relation to the extendedsurfaces of the condenser tube whereby to reject heat through suchsurfaces by radiation during periods of compressor inactivity, thecondenser and its aforesaid extended surfaces being exposed to aircirculation and the size of the capillary being such as to dischargerefrigerant freely during the initial period of compressor operationbefore said heat absorbing means is appreciably increased in temperaturewhile retarding the amount of refrigerant passing through the tube asthe temperature of the refrigerant rises due to the heating of saidabsorbing means.

32. A device as defined in claim 31 in which the heat absorbing meanscomprises a closed liquid circulatory system in heat exchange relationto the refrigerant condenser tube and said surfaces.

